Automatic die-press stopping mechanism



, April 24, 1928.

c. D. MCDONALD AUTOMATIC DIE PRESS STOPPING MECHANISM Filed Aug. 8, 1927 2 Sheets-Sheet 1 April 24, 1928. -.l,666,942 I c. D. MCDONALD 1 AUTOMATIC DIE PRESS sTbPPmc uEcnAiIIsu Filed Aug. 8. 1927 f 2 Shuts-Sheet 2 F I 3 .fi'j' C 42 z/enion 67mm 652%?0/264Z5,

Patented A r. 24,1928.

U NiT ED' P 3 Pi v 'cally operated mechanism forholding-the 5 hand lever of. the pressv st in operative or starting for releasing said hand lever Mcnon inin; oromciieo; I

CHICAGO, ILLINOIS, a onronmma or InLInoIs'i I ILLINDIS, AssmaoR cromachine we AUTOMATIC mn-rmiss s'rorrxn'e MECHANISM.

vApplication filed August 8, 1927; Serial lie, 21 1, i 6 9 press stopping mechanism and object is to provide ping mechanism position and and thereby stopping its principal. improved pneumatr arting and stop the pressin case an abnormal condition arisesin any ofthe passage ways through' wliichthe work moves. Part of the subject matter disclosed in this application has been continued from a c,0- pending applic'ationfor patent on auto inatic die press stopping,inechanism filed present inventio by mmezin the on February 11 192 167,412,

United States. Patent .Ofiice under Serial No.

The present invention has reference more particularly to anautomatic die press in which strips of material are inserted; oneat] a time from a stack of strips,

and therein fed in a step by step manway nor to the dies of the press,

either .by blanking out otherwise as is well are operated upon, pieces therefrom-,5 or

into a feed where the strips understood, the blanked out pieces being discharged through a discharge chute "and delivered to other" meeh operation;

the feed way, in which Occasionally anism for subsequent 'inore' than one stripof'mater'ial is accidentally inserted -1I1t0 case it becomes necessary to stop the press and'eXtr-act the superfluous strip, f and one be automatically stopped.

the press in case: of

hereby the press will Sometimes the blanked out articles pile up in the discharge chute, which makes it necessary to stop the press and relieve the congestion and one of the objects of the pr esent invention to provide improved pneumatic means for 1'6 leasing the starting a tages in view, this inve nd stopping "lever in case ofsuch an emergency to thereby auto matically stop the press. i

With these and other objectsand advan ntion consists in autostartilng andstoppinglever of press starting and stopping mechanism",- said'nnechanism located at the passage also embodying means:

the-objects of the v n is to provide improved pneumatic meansfor releasing the starting;

hand lever, or

position sojlong as, vacuum s' maintained ins the suction end 'of thehead; together with meanslocated at the feedivay or I other passage way for the,material;and:operatingto release the vacuum-inthe Vacuuinhead when an emergency occurs iin said feedway or otherpassage way. "The invens t ion further-consists in a vacuum-head having a suction end arrangedsetojcontact with the'handleVer of the press-starting and stopping mechanism and means for releasing the vacuum insaid-vacuum head, which means are controlled 'by' the number of strips which enter the feed way at one time or the number of ,blankedarticles that pass through the discharge, chute. The 1 invention't'urther consists in the severalnovel' teatures of constr uction arrangement and com-' bination of parts hereinafter fully .set forth and claimed. V V The invention is clearly illustrated inthe drawings accompanying th'is. specification, in which? diepress' partly bioken'away and stripped of much; ofthe press mechanism and showing 'aisii'nple embodiment of the present in-' 'vention applied to the hand leverof the ,startingand:stopping; mechanism; Fig. 2 is a'view, .partly'in side elevation andpartlv in central longitudinal section, of vthe vaciium head and a fragment of the hand lever.

Fig. 3 is a-v-iew of thefeed table andassociated parts and showing, one of the vacuum release means employed in connection with the feed wayythe view beingtaken in the direction ofthe arrow- 3"'in Figsflf and 4-; Fig; 4 is a detail vertical cross section taken on the line 4-4 of Fig. 3; Fig.5 is a fragmentalE vertical section taken through the di's'cha'rgechute; Fig;6,isa'side elevation of the vacuu'm release mechanism associated with the discharge chute and Fig. 7 is a vertical section taken on the line 77 of Fig. 6.

Referring to said drawings, which illustrate a. simple embodiment of the present invention applied to an automatic die press of conventional form, the die press body is seen at 10 and said body supports the various operating mechanisms of the die press.

A press of the type illustrated is more fully shown and described in my prior Patents No. 1,252,278, dated January 1, 1918, and No. 1,529,031, dated March 10, 1925, to which reference is made herein. As is well understood presses of this type are equipped with clutch mechanism 28, whereby a continuously rotating drive pulley (not shown) may be operatively connected and disconnected from the crank shaft 21 which operates the ram 22 of the press. The presses are 7 also equipped with brakeinechanism 23 for applying a braking-action to said crank shaft whenever the clutch is disconnected; As in my prior patents above referred to" the combined clutch and brake mechanism is controlled from a hand lever 11, fulcrumed upon the press body at 12 and connected to the clutch and brake mechanism by a link 14, an operating strut 13 and links 15, 16, as is well understood. These parts are so proportioned and arranged that when the hand lever is in its upper or starting position wherein the press operates, the center line between the ends of the link 14L has not passed the fulcrum 12 of the hand lever 11 whereby whenever said hand lever is released from itsop'erative or starting position as shown in Fig. 1, itmay fall by gravity, therebyactuatingihe clutch and brake mechanism to disconnect the clutch and apply the brake and consequently stop the press. .At the side of the press body opposite the one seen in. Fig. 1 is the feed table 17 of the press. Said feed table has a feed way 1.8 in its upper side through which the strips of material a, are fed to the dies 24, The feed way 18 is located between the top member. 19 of the table and a bar or plate 20 (see Figs. 3 and 1) and finger bar mechanism (not shown) is mounted in a guide way in thefeed table and is arranged to feed the strips of material towards the dies 24, 25, in a step step fashion as is well understood. i

Secured upon the side of the press body adjacent the hand. lever 11 is a vacuum head 82, which contains an air passage or conduit 33 that leads from its suction end 36 to a vacuum pipe 34. The vacuum pipe leads to suitable source of vacuum supply, and in case the press is provided with a vacuum pump it may lead thereto, otherwise it may lead to a vacuum tank 85 connected with a suitable vacuum pump (not shown).

part 38 of the hand lever whereby when a 7 partial vacuum is created in said' suction end of the vacuum head the hand lever will beheld against its suction end until the vacuum is released in the vacuum head or the lever forcibly disconnected therefrom. In the conduit or air passage 33 is a spring pressed valve 39 which is adapted to seat upon a valve seat 40 in the conduit 33 and thereby close the passage through said conduit and said valve 39 is mounted upon a valve stem 11, which may protrude from.

the suction end of the vacuum head. "The part 38 of the hand lever engages with said valve stem 41 whenever the hand lever is raised to its starting or operative position, whereby the valve is unseated and the passage from the vacuum pipe 34 to the suction end is thereby opened. WVhen the hand lever is released from the vacuum head, the valve 39 closes the passage through the vacuum head and prevents any leakage of air' at this point. A coiled compression spring behind the valve operates to seat it upon its seat whenever the hand lever is moved away from the valve stem 11. It, will be observed that so long as a vacuum extends to the suction end of the Vaeuumhead the hand lever will be effectivelyheld in its starting or operative position, but that in case the vaccum in said suction endof the vacuum head is released, the hand lever will be permitted to fall and thereby actuate the clutch and brake mechanism to stop the press.

Leading away from the conduit or air passage 33 is a vent-tube 42 which has branches connected with vacuum releasemechanisms which are set in operation whenever'an abnormal condition arises in the feed way or in the discharge chute or any other vulnerable spot in the press where such vacuum release mechanismis located. Y

The vacuum release device or trip device (so called in my co-pending application above referred to) which is operated by a superfluous number of strips entering the feed way 18 is shown in Figs. 3 and 4t and comprises a trip pin 51 slidably mounted in a guide sleeve 52, which is'formed with a part 53 that is bolted orotherwise secured to one of the brackets 54, whichcarries the strip lifting and inserting mechanism (not shown) of the press. Said part '53 of the guide meme ment means for afiording a close-adjustment The between'the lever 57 F and trip pin 51".- extent of movement of. the long-arm: of the lever 57, (which engages" with the valve stem) is considerably greaterthan the'extent' ofmovement of that part or the lever which is engagedby the trip pin 51, whereby: slight movement of the trip pin (such 'as is caused by more than: one thickness ofmaterial pass ingv under the tripjpin-"i will 'cause-arelatively longmovement of the outer enact the rial are fed one'at a: ti

sufiicient to open lever 57, the extent of such inove'ment being. theair-valve or vent device 56, and admit air to the vent tube 42. As has'been explained the strips ofmateme to :the dies .24, 25, where the articles are blanked out of the strips. Said articles fall upon adischarge chute 26which conveys them to other mechanisms for subsequent treatment. The discharge chute: usually in the form of a trough like device, and ata: place adj acent the receiving end of the discharge chuteisa pivot-- ally mounted trip mei ber 27 under which the stamped out articles pass on their way to the discharge: end of the discharge chute-r The trip: member may beginthe': form ofa strip or barof material mounted upona rock shaft 28' which is 'journaled'in'brackets se-v cared to the sides of the; dischargeehute;

Suiiicient clearance is left between the lower" end of the trip member 27. andbottom of the discharge chute: to-permit the blankedout articles to'pass :freely,one at a time. under the trip member; However, in

slightly and cause" in the: branch 42 v opened, thereby-breaking the vacuumin the suction end o'f the vacuum head'32 andperthe vacuum in mitting. the hand lever press. As illustrated in the drawings, the

rock shaft 28 of the trip member 27 has' a' the arm 30is consequently movedin a direction to unseat the valve member 31 from the vent opening in the vent tube device 29 thereby permitting air to rush in and break the suction end of the vacuum tube.

57 and contacts with the case the articles; pile up in the discharge chute aitcr'leaving. the dies they swing said tripnieinberupward: a valve or vent device 29 of the vent tube 4-2 to be:

11 to fall and stop the -In the operation of the automatic pressstopping mechanismabove described the hand lever 11 is manually raiisedqintozcontact with the suction end'of the vacuu-rn head" 32 as seen in Figs.- 1 and 2, thereby, throws in g the clutch and brake mechanism into the position wherein the press is started. -Du.ring normal conditionsinlthe' feed way andin the dischargechute, the press continues to run, but in case'more than one strip of material is inserted into the feed way 18,.the trip pin:51' is'thereby raisechthe air valve or vent device: 56 thereby opened, I air admitted throughtheibranch 42 and vent tube 42 -to the suction end'iof' the vacuumhead 32, the

ticlesipile up in'the discharge'chute the trip;

, member-27 is raised and the vent opening n the end of the vent tube. 42 is-therebyuncovered permitting air to enter the vent tube.

42 and break the vacuuminthe suction end" ofthe' vacuum head, consequently permitting the hand lever to fall and stop the'press as before; The attendant.thenrelieves the'jam in the discharge chute and lifts the hand lever as beforeltostart the press;

More orless variation of the exact details of construction is possible without departing from the'spirit of this invention; I desire, thereforefnot to limit myself to the exact vacuum insaid-end is released and the hand vacuum head." Inacase the blanked0ut,a1''-- form? of theconstru'ctionshown andv de-r scribed, but intend; in the following claims,

to point out all of" the. invention. disclosed:- hereiml. I Y 1 j Y I claim as new, and desire-.tolsecureby Letters Patent? 7 I 1. Automatic die press stOp ing mechanismi'or die presses having a passage way for thework, comprisingn combination,

the hand l'ever of' thepress starting and" stop ping mechanism, a vacuum." head. having a suction end engaging; said handlever where by said hand: lever is supportedin its raisedor. starting position when vacuum is created" in the su'ction' end ofsai'dvacuum head; said vacuum head being connected to a; source oi:

.va cuumsupply, a vent tube leading from said-vacuum headand having anair vent therein,fand ain'orma lly inactive trip device for opening said air'valve, whichgtrip is made operative under an: abnormal condition aris-' ing: in said. passageway.

I $2.:Automatic die pressi stopping; mechanism for die presses having a passage way for the work, comprising in combination, the hand lever of the press starting and stopping mechanism, a vacuum head having a suction end engaging said hand lever whereby said hand lever issupported in its raised lever of the press starting and stopping mechanism of a die press having a strip feed.

way, a vacuum head having a suction end arranged to contact with said hand lever,

wherebythe lever is supported-in starting position when vacuum is created in the suction end of said vacuum head, saidvacuum head being connected with a vacuumsource, a vent tube leading from the suction end of said vacuum head and having an air valve thereon, a normally inactive trip device associated with the strip feed way of the press and having a valve actuating member operating to open said air valve when an abnormal condition arises in the feed way.

4. Automatic die press stopping mechanism for presses having a strip feed way, comprising in combination, the hand lever of the press starting and stopping mech anism, pneumatic means engaging said hand lever whereby said hand lever is supported in its raised position when vacuum is created in said pneumatic means a vent tube leading from said pneumatic means and having an air valve thereon, and a normally inactive trip device for actuating said air valve, which trip device is made operative under an abnormal condition arising in the strip feed way of the press.

5. Automatic die press stopping mechanism, comprising in combinatiom the hand lever of the pressv starting and-stopping mechanism of a die'press having a strip feed way, a vacuum head having a suction end arranged to contact with said. hand lever, whereby the lever is supported in starting position when vacuum is created in the suction end of said vacuum head, said vacuum head being connected with a vacuum source, a vent tube leading from the suction end of said vacuum head and having an air valve thereon, a normally inactive trip device associated with the strip feed way of the press and having a throw amplifying lever operating to open said air valve when an abnormal condition arises in the feed way.

6. Automatic die press stopping mechanism comprising in combination, the hand lever of the press starting and stopping mechanism of a die press having a strip feed way, a vacuum head having a suction end arranged to contact with said .handlever, whereby the lever is supported "in starting positionwhen vacuum is created in the suction end of said vacuum head, saidv vacuum head being connected. with a vacuum source, a vent tube leading from the suction end of said vacuum head and having an air valve thereon, a normally inactive trip. device associated with the strip feedv way of the press and having a trip pin extending into the feed way and a throw amplifying lever engaging said pin and operating to open said air valve when an abnormalcondition arises in the feedway. I i V 7. Automatic die press stopping mech anism, comprising in combination, the hand lever of the press starting and stopping mechanism of a die press havinga strip feed way, a vacuum head having a suction end arranged to contact with said "hand lever, whereby the lever is supported in starting position when vacuumis created in thesuC-L tion end of said vacuum head, said vacuum head being connected with a vacuum source, a vent tube leading from the suction'end of said vacuum head and having an air valve thereon, a normally inactive trip device as sociated with the strip feed way'of the press and having a trip pin extending into the feed way and engaged by a superfluous number of strips passing under the. pin, and opcrating to open said air valve when an abnormal condition arises in the feed way.

8. Automatic die press stopping mechanism, comprising in combinatiomthe hand lever of the press starting and stopping, IDGClIEIIHSIH of a the press having a strip feed way, a vacuum head having a suction end arranged -to contact with said hand lever,

whereby the lever is supportedin starting.

position when vacuum is created in the suction end of said vacuum head, said vac-. uum head being connected with a vacuum source, a vent tube leading from the suction.

end ofsaid vacuum head and having an air valve thereon, a normally. inactive trip device associated with the strip feed way of the press and having a trip pin extending into the feed way and engaged by a superfluous number of strips passing under the pin, and a throw amplifying lever engaged bysaid pin and operating to open said airvalve when an abnormal condition arises in the feed way. I CHARLES D. VBICDONALD." 

